TCS Daily

TCS COP11 Coverage: Media Fish Fry

By Gary Sharp - December 6, 2005 12:00 AM

The week before Thanksgiving, the World Wildlife Fund, an environmental NGO got what it wanted in the lead up to the United Nations' latest meeting to discuss climate change, taking place in Montreal -- scary stories about dire effects from global warming.

"WWF: World's Fish Are In Hot Water," CBSNews reported. "Group: Higher Water Temps Threaten Fish," intoned ABCNews International and MSNBC. "Global Warming Threatens Fish," FoxNews declared. All the major networks carried headlines about the WWF's report: Are We Putting Our Fish In Hot Water?

The report itself was filled with lots of glossy pictures, lots of information on the importance of fishing to diets and the world economy, and lots of scary speculation about what might happen if waters are allowed to warm more than 2 degrees Celsius.

The only thing lacking was scientific documentation to warrant such a media frenzy.

If the media really wanted to know what is going on with fish it might have attended the International Council for the Exploration of the Seas 2004 workshop, "The Influence of Climate Change on North Atlantic Fish Stocks," in Bergen, Norway, or at least reviewed some of the more than three dozen scientific studies and reports presented there. Then they would know how simplistic and misleading WWF's generalizations are.

Consider WWF's supposed fishery expert Katherine Short's bald statement: "The balance is set to tip, as climate change continues the pressure on fish populations already strained by overfishing, pollution and habitat loss."

What fish populations is she talking about? Salmon? Arctic char? Cod? Haddock? Tuna? All of them are reviewed in the 2004 workshop, and there was no evidence that man-made climate change is or will have any major impact.

What will have dramatic consequences are the very things she puts climate change ahead of -- habitat loss, pollution, and overfishing. More specifically the past manipulations of freshwater fish habitat are far more influential than anything else, as J. Gessner and R. Bartel describe very well in their article "Sturgeon spawning grounds in the Odra River tributaries: A first assessment." That study, in the Boletin Instituto Espanol de Oceanografia in 2000 looked at barriers created over centuries within sturgeon habitat that has left them with no options for migrating as climate changes.

If you want to help the sturgeon, you don't fight to keep the climate "stable"; you get rid of the barriers to their migration or otherwise increase their options as climate varies.

This makes sense if you think about it at all. Ecosystems are rarely if ever "in balance" so as that they can be "tipped" in the silly way WWF describes. Climate has constantly changed naturally through the millennia, in both long cycles such as Ice Ages and multidecadel Pacific oscillations and shorter Decadal ones (PDO). Then there are longer term trends in frequencies of El Nino and La Nina events, adding 'noise' to the annual seasons.

Europe and Scandanavia, for example, have experienced a natural climate shift since about 1987, as documented by scientists from the Baltic Seas Research Institute, Latvian Fisheries Research Institute and Danish Institute of Fisheries Research. This shift is affected by the naturally recurring North Atlantic Oscillation, and any plan to protect fish stocks must take that reality into account.

Now, scientists have noted the stunting and poor reproduction in most high latitude fish, both marine and fresh water, as a result of millennia of repeated encounters with regional climate change. These fish have adapted to their environments by migration or, in some cases, genetic mutation, especially for those unable to migrate in highly dynamic environments. Lionel Johnson, in his 1981 paper, "The Thermodynamic origin of eco-systems," described the responses he observed in Arctic lakes to various climate-related phenomena over time. He found the Arctic char, the only fish in these lakes, was quite adaptive, and that the older fish were almost always of smaller size than those that were quickly lost in stress situations -- a lesson often missed by those such as the WWF's Short who over-generalize.

An array of research communities, from Russia, Europe, Canada, Africa, South America and elsewhere also are providing a more realistic perspective on what climate changes have occurred in fishing habitats over decades and centuries, and how those changes have affected fish stocks. J. Luterbacher, D. Dietrich, E. Xoplaki, M. Grosjean, and H. Wanner in "European Seasonal and Annual Temperature Variability, Trends, and Extremes Since 1500," have helped clarify the bases for most species' adaptability, and behaviors.

Linked within my own site's Fisheries Timeline is a figure at the top of the 21st Century Fish page that provides a culmination of several decades of study by Russian Arctic Institute researchers. This chart of their Atmospheric Circulation Indices (ACI), overlain onto major fisheries catch records was first brought to the public's attention by Leonid Klyashtorin of VNIRO, in Moscow, and the ACI has been updated routinely since the 1940s.

What the chart shows is that there are indeed periods when fish populations can be influenced by changes in climate. Both warm species fish and the alternative cool preference species are depressed during "transition periods." But it's important to understand what that means.

Since the 1983 Food and Agricultural Organization's Expert Consultation to Examine Changes in Abundance and Species Composition of Neritic Fish Resources in Costa Rica, the general emergence of these well timed, mostly cyclical patterns has provided a more or less practical means for forecasting when the "transitions" will occur. Since then, many of us who worked at the conference have been waiting for fisheries managers to step up and accept a simple fact -- that these dynamics are not "manageable," as the WWF would imply. They are no more under human control than the sun in, its hurtling through the universe, is controllable by man. These processes have been going on for millennia, and the species involved, if not prohibited from using the available options, will respond, and survive until their requirements are restored -- over time -- if someone has not blocked access to or otherwise physically scrambled some critical habitat

It is important to note that there is little common ground in what has been the result of millennia of climate change processes in either the North Atlantic or North Pacific. Among the better examples are those involving comparisons of the salmon populations.

As glaciers rimmed both regions until only 10,000 to 11,000 years ago as far toward the equator as 45oN latitude, there was no access -- no rivers -- for the fish to migrate there. The present population of fish there can best be explained as a positive result of the Earth's warming since the last Ice Age ended. In that period of warming, the five species of salmon in the Pacific have thrived, and in fact recolonized the entire North Pacific, and well into the Arctic, ranging from Baja California north and west to Alaska, Russia, and southward to Korea. Their genetic variabilities are richest in their southernmost ranges.

Indeed, warming has clearly been beneficial to their stock, as a study by C.L. McLeod and J.L. O'Neil in a 1983 Canadian Journal of Zoology, showed. They reported findings between 1978 and 1981 of chum salmon in the Liard River system in the Northwest Territories and British Columbia, demonstrating an extension of the salmon's range thanks to more favorable conditions. And Bruce P. Finney, Irene Gregory-Eaves, Jon Sweetman, Marianne S.V. Douglas, John P. Smol in the Oct. 27, 2000, Science, "Pacific Salmon over the last 300 years," found increased salmon runs in Bristol Bay and Kodiak Island regions of Alaska during warmer periods versus colder ones.

Meanwhile, the single salmon species in the North Atlantic comes and goes from the Arctic regions well southward, during various time scales, as per Lajus et al, presentation at the 2004 Bergen meeting. These comings and goings are indeed linked to climate regime shifts, and warming simply opens new options, while closing a few to the south.

These are known facts, and should provide positive perspectives, not gloomy bits that focus on the wrong end of the problem. Warming is not necessarily bad for fish. Shutting down normal options, such as access pathways, is bad. So, what to say about the media frenzy engendered by the WWF's phony climate threat to fish? It seems that the fish species have greater capacity to cope with their environments than the media are capable of dealing with demonstrably silly, misleading, unscientific scare stories.

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